Gauge for determining internal diameter of elements being ground



Feb.- 2 ,1926.

' T F. J. PRATT GAUGE FOR DETERMINING INTERNAL DIAMETER OF ELEMENTSBEING GROUND Filed Jan. 17, 1924 Patented at. .2, i92

UNITED STATES PATENT OFFICE.

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GAUGE Ion nnrn'mrmme m'rnmmn mailman or ELEMENTS-mints enounn.

-Applioation filed January i7, i924. Serial No. 086,988.

I same, reference bein had to the accompanying drawings, whic form apartof this specification. My inventionrelates to a gauge for automaticallymeasuring the bore or internal diameter of an element being ground.

One object of the preserit'invention is to provide a device which willinsure accuracy of measurement throughout the entire length of theelement calipered while 'the latter is being round to size.

\ A further ob]e ct of the invention is to increase production due tothe speed with which-articles may be ground without stopping thegrinding machine to take measurements. I.

A further object is to provide a device so constructed and mounted thatit may main.- tain its proper relation to the article being groundthroughout the entire period of grinding.

A further object of the invention is to provide a device which may be'swungout of the way to remove or replace the article to be ground.

A further object of the invention is to provide against any appreciablewear even after long periods of service in traversing the bore orelement calipered,-by

employing diamonds, sapphires, or other gem stones for the styluspoints.-

One object in constructing the stylus points of diamonds' is that theymay break through the fluid film covering the surfaceof the elementbeing ground that an exact measurement may be obtained without cuttingor scratching the surface measured.

A further object of the invention is to provide a device which isreadily adjustable to meet the requirements of different articles to becalipered. a

With the foregoing and other objects in view which will appear as thedescription proceeds the invention further resides in the combinationand arrangement of parts and in the details ofconstruction hereinafterdescribed and claimed it being understood that changes may be made inthe precise embodiment of the invention herein disclosed withoutdeparting from the spirit of the same. L In the drawings accompanyingthis specification:

Fi re 1 is an end elevation of the device attac ed to a grindingimachineshowing the article to be, ground in contact with the rindinwheel,indicated in dash and otted lines.

Figure '2 is a plan view offthe device,

with the dial indicator removed, secured to a fragmentar portion of theframe of a grinding mac ine as it would appear when .measuring the hereor internal diameter of an element being ground,a fragment of 75 whichis shown in cross-section.

Figure 3 is a plan and sectional view of the device taken on or aboutline 3-3 of Figure 1, indicating the stylus arms of the gauge swung outof operative position 5- showlng a fragment of the grindin machine andsectional view through the article being ground,as in Figure 2.

Referring now to the letters of reference placed upon the drawin s:- 1 a-A, designates a grindin machine, B,-denotes a grinding wheel, anarticle being ground and calipered.v

D, represents a pulley and E indicates the driving belt.

F, denotes a bracket bolted .to the frame of the machine and Gdesignates a socket member pivoted at F to the bracket adapted toreceive a standard or red G, secured in the socket member by a set screw9;

G denotes an arm integral with the socket member, slotted at its lowerendjto receive a bolt G screwed into the bracket F.- G indicates aspring sleeved upon the bolt adapted tobear upon the arm G to normallyrestore the rod G to a vertical or predetermined position. G representsan adjustable set screw extending through the arm G adapted to bear uponthe bracket to limit the movement of the rod under the urge of thespring G H, designates a divided clamping'member adjustably secured tothe upright rod G, by a bolt H.

Extending transversely clamping member H, and secured thereto by a boltH is a bracket arm I, provided at through the one. end with a, yoke; Iin' which issupported by 'a pair of adjustable pivot screws J, .J, abracket K having a forwardly extending arm K, and'.proj ect ing fromupper face adjacent 1ts end is a lug K adapted toreceive-fa swin in yokearm L, pivoted to the bracket pivotal bolts L, L,the outer .end of theya pair of gyoke arm L, being formed with a divided Q bearing -u on theinclined or beveled "walls of thes o'tted arm R, represents a diamond orem stone mounted in the end of the arm ,-:wh1ch is adapted to contactwith the periphery of the element to' be ground.

' upon the peripheryof the work The lower end of the bar M, is fittedwithfa divided clamping blocks, adapted to receive a bar T ad ustabletherein on theforw-ard end of which is mounted a-slotted arm T,adju'stably secured to the bar bya set screw. T".

-R", denotes a diamond or gem stone set in the end of the slotted bar Tto impinge emg ground.

U, represents 'abracket member clamped to the upper end of the bar M bya bolt U having an arm U to which is clamped an indicating dial W, ofusual construction,

the depending finger W of the indicating dialcontrolling the movement ofthe swing ing pointer W?- which bears upon an arm X, having aoke-"shaped end X pivoted to the bracket {1, bya pair of pivotal screwsIntegral with the arm'X, is an extension )0, adapted to support anadjustable slotted arm Y, to which. it is secured by a .set screw Y".

- R", denotes a gem stone-fitted to the endof the slotted ar Y, toimpinge upon the periphery of the work to be calipered.

For the sake of convenience the device may be said to consist ofasupport, an adjustable frame on the support comprising the bracket armL. yoke member I, bar U and vertical standard M on which the armscarrying the gems are adjustably mounted, the member N'being capable ofoscillation .in the yoke member to swing the adjustable arms toward andaway from the work;

Having now indicated the several parts by reference letters theconstruction and operation of the device will be'readily understood.

A template or master element (not shown) upon the. periphery of theelement mounted in the grinding machine. The grinding gauge is thenadjusted to the position indicated in Figure 1-, in which the oppositelydisposed diamond points R and R", supported respectively by the arms Tand Y, may impinge .upon the inner surface ,ofthe template on a planeintersecting its longitudinal axis,the arm Q being adjusted so that thegem stone R, will impinge upon the internal periphery of the template,midway between the gem stones R and R". In adjusting the gem stones toimpinge upon the periphery of the template, care should be exercised toinsure the rotatablepointer W of the dial indicator W, re 'istering atzero,it being evident that w en the element to be groundds inserted inthe grinding machine in place of the template the pointer will move from..of predetermined internal diameter is first.

its zero position to a point'indicating the relatlvely smaller diameterof the element to be ground.

The gauge having been properly adjusted thefdevice is swung horizonta yupon its pivotal support J, J, to the position indicated 1n Figure 3,thetemplate is then removed from the grinding machine that it may bereplaced by the element to be ground. The gauge is then returned to itsformer position, as indicated in Figures 1 and 2. Power is then appliedto actuate the grinding machine,the operator taking careful note of thedial indicator reading as it -of the template. The gauge supportingframe-is then again swungto the position indicated in F1gure'3- that theelement ground may be removed to be replaced by another element to beground-whereupon the operation just described is repeated.

To maintain the gem stone R carried by the arm Q in impinging relationwith the periphery of the element bein ground the spring (ir mountedupon t e bolt G screwed in the bracket F, is adapted to bear.

upon the depending arm G integral with the socket G in. which theupright rod G is mounted. The action of the spring causes the rod G totilt causing the. arm Q to move laterally that its gem stone B may iminge emg ground as the diameter of the bo e is graduallyenla g g g indng The ada frame comprising a plurality of adjustable elementsconnectedtogether to form a unitary structure including a plurality ofindependently adjustable armsi secured 'to the frame at one end, meansconnecting the arms to the frame for oscillation into and out of anelement to be internally ground, a gem stone mounted adjacent the otherend of the respective adjustable arms and adapted to impinge. upon theinternal periphery of the element being ground, resilient means adaptedtoact upon the frame, whereby the gem stones may beheld in impingingcontact with the surface ofsaid element while being ground, anindicating device and means for actuating, the indicatin device, wherebya gauge reading may be 0 tained to determinechanges made in the diameterof the bore of the element being ground while being acted upon by arinding wheel.

nal diameter of an annular element while thesame is being ground, meansattached to a grinding machine for supporting a frame, a framevertically adjustable upon said supporting means and including, anoscillating member, a plurality of arms, vertically adjustable upon theoscillating member, elongated members adjustably'carried by said armsfitted with gem stones and adapted to bear-upon the periphery of thebore of the 1 annular element, a dial indicator, and means for actuatingthe indicator, whereby a gauge reading may be obtained to determine'changes made in the diameter of the bore of the annular element whilebeing ground.

3. In a device of the character described, a bracket adapted to besecured to the frame of a grinding machine; a standard pivoted to thebracket provided with a depending arm; a bolt pro ecting from the wallof the bracket extending through an opening in the arm; a spring mountedupon said bolt adapted to bear upon the arm to tilt the standard; meansfor limiting the tilting action of the standard; a yoke-shaped elementv'erticall adjustable upon saidv standard; an oscil atingframe ivoted insaid yokeshaped element including awertically disposed member; aplurality of adjustable arms secured to said vertically dis osed member;bars adjustable laterally o and secured'to said adjustable arms, thesaid-bars having a gemstone fitted to one end of each bar and adapted toimpinge upon the inner wall of an annular element to be ground;

a dial indicator and means actuated by one of the adjustable arms,whereby a gauge reading may be obtained of the internal ele- 'ment whileit is being ground. 2. In a device or determining the inter- 49In adevice of the character described, a standard, a framemeans connectingsaid frame and said standard said frame including a vertical rod, anbeing capable of oscillation on said connecting means toward and awayfrom the work, a plurality of independently adjustable I arms onsaid'rod, and means on the adjustable arms for en-' gaging the interiorof the work while being ground. I a v In testimony whereof, I sign thisspecifi- I cation.

FREDERICK JACKSON PRATT.. i

